package cn.jiahua.test20;

import java.util.concurrent.TimeUnit;

public class Test {

    private volatile static int  num=0;

    public static void main(String[] args) {

        new Thread(()->{
            while(num==0){

            }
        }).start();


        try {
            TimeUnit.SECONDS.sleep(1);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }

        num=1;
        System.out.println(num);

    }

}
